The QNX Neutrino Persistent Publish/Subscribe (PPS) service is a small, extensible publish and subscribe service that offers persistence across reboots. It's designed to provide a simple and easy-to-use solution for both publish/subscribe and persistence in embedded systems, answering a need for building loosely connected systems using asynchronous publications and notifications.
With PPS, publishing is asynchronous: the subscriber need not be waiting for the publisher. In fact, the publisher and subscriber rarely know each other; their only connection is an object that has a meaning and purpose for both publisher and subscriber.
Figure 1. A complex application that uses PPS to share information between components.QNX Neutrino also supports the D-Bus message-passing system. See “D-Bus” in the Utilities Reference).